Magnetic vibratory switch



S. F. JAMES ET AL MAGNETIC VIBRATORY SWITCH Filed Aug. 17, 1945 Patented Jan. 2, 1951 MAGNETIC VIBRATORY SWITCH Stephen F. James and Esther D. James, Chicago, 111.

Application August 17, 1945, Serial No. 611,030

3 Claims. (01. 200-90) This invention relates to improvements in vibrators.

The main objects of this invention are to provide a new and improved vibrator which is simple in construction, more compact and smaller in design, inexpensive to manufacture and will operate for long periods of time without attention; to provide a vibrator of the character having a relatively short reed; to provide a vibrator of this type which is free of the usual contact bounce; to provide a vibrator of this type wherein the contact arms do not traverse any portion of the arc traversed by the reed; to provide a vibrator of this character having a reed which will be free to swing its full arc and eliminate transfer of secondary frequencies to the reed above the reed contact arms during operation; to provide a vibrator of this type having one fundamental and operating frequency which will produce the desired frequency response and maintain it within throughout its life; to provide a vibrator of this character which employs a laminated frame and pole piece and has a pair of oppositely positioned contact arms on the reed extending at right-angles thereto at the base of the reed, whereby to prevent any transfer of harmonics to the reed, and also resulting in positive opening and closing of the contacts.

An illustrative embodiment of this invention is shown in the accompanying drawings in which:

Figure l is a side elevational view of the vibrator of our invention.

Fig. 2 is a sectional view taken on line Fig. 1.

Fig. 3 is a front elevational view of the structure shown in Fig. 1.

Fig. 4 is a front elevational view of a modified form of construction.

Fig. 5 is a front elevational view showing a further modified form of construction.

Referring in detail to the drawings, the frame is made up of a series of laminations I, 2, 3, 4, 5 and 6 as shown in Fig. 2, preferably formed by stamping the same out of a high grade of transformer steel, so as to consist of a vertically disposed arm I, a horizontally disposed arm 8, a vertically disposed pole piece 9 depending from the horizontal arm 8 and is in a plane parallel to the plane of the arm 1; and a horizontally extending base portion H).

An electromagnet ll, wound with the usual energizing and de-energizing coils is attached to the said pole piece 9, in the usual manner.

The base or bottom portion of reed I2 is secured in the base In between members 3 and 4 and the laminations I to 6 inclusive and the base of the reed l2 are integrally secured together in any suitable manner such as by bolts M-i 5, as will hereinafter be more fully explained. The reed I2 is preferably constructed of high grade spring steel and is provided with a transversely extending slot I3 adjacent its lower end. An armature or weight l6, which preferably is formed of a metal of semihigh retentivity, is aflixed to the upper end of reed l2 in the usual manner.

Stationary inverted L-shaped contact arms "-18 are secured to the base it), one on each side thereof and spaced apart therefrom by mica spacers l9 which are positioned one on each side of the base of each arm I! and I 8, as clearly shown in Fig. 3. The base portions of contact arms I7 and I8 and the spacers H! are all provided with aligned apertures which correspond with the aligned apertures in the laminations in the base portion l0, the apertures adjacent the bottom of reed l2, and the apertures in metal end spacers l9, whereby to receive the bolts l4-I5, which, when drawn up, will hold the structure together as one compact integral unit.

It will be noted that the upper ends of contact arms l'l-IB extend in a horizontal plane and at right-angles to the reed l2, one on each side of said reed. Contacts 20-2! are aifixed to the upper surface of the contact arms ll-I8 respectively in any suitable manner, such as is well known in the art.

The movable contact arms 22-23 are each provided with upwardly extending portions 24-25 respectively which are positioned one on each side of the reed l2, directly above the slot l3 and each is provided with aligned apertures therein corresponding to apertures in reed l2, whereby rivets 26 may be threaded therein and secure the arms 22-23 to the reed I2. Each contact arm 22-23 is provided with contacts 28-29 respectively and which are affixed to the underside thereof in any suitable manner, such as is well known in the art.

The two pairs of contact arms l1-l8 and 22- 23 are parallel to each other and are spaced away from each other. The contacts 28 and 29 are positioned directly above contacts 20 and 2| respectively and are slightly spaced away from each other, whereby the contacts 20 and 2| are adapted to be engaged alternately by contacts 28 and 29 which are mounted on the reed l2.

It will be noted from Fig. 3 that the free ends of laminations I, 2 and 3 forming the pole piece 9 are shorter than the free ends of laminations 4, 5 and 6, and that the weight l6 lies directly under the laminations I, 2 and 3 when vibrator is at rcst. By this arrangement a new phenomenon has been discovered, i. e., the polarity, once established, is constant. The free end of the pole piece 9 is always "north and the portion I of the frame is always south. The righthand end of the weight It (see Fig. 1) is always south and the left-hand end is always north. This is the opposite of vibrators now in use, since in them the poles of the reed weight are constantly changing upon every swing of the reed. In the case of push-pull circuits, the free end of the pole piece 0 arid the portion 1 of the frame changes polarity every half cycle but the polarity of the reed weight remains constant.

By this arrangement it will be noted that the reed I2 is free to swing in its full length, and eliminates transfer of secondary frequencies to the reed, above the mounting of the contact arms, as the reed bends its full length, instead of a reduced portion as in the prior art constructions, when the contact is closed. It will also be noted that the reed of this invention has eliminated all the usual dead weight and bouncing interference of the prior art construction.

Because the contact arms are constructed of relatively rigid material and are placed at rightangles to the reed at the base, no yield or bounce is necessary to maintain constant amplitude of the reed. This type of construction will produce a constant frequency, permitting the reed to produce the sound of a musical note at a frequency up to 800 cycles and may produce frequencies considerably higher.

In the modified forms of construction shown in Figs. 4 and 5, the constructions are identical in every detail as disclosed in the preferred embod ment expect for the movable contacts, i. e., those mounted on the reed.

In Fig. 4 the vertically extending portions 4.! and 42 of the contact arms 43-44 respectively extend downwardly instead of upwardly, as in the preferred embodiment.

In Fig. 5 the movable contact arms 5! and 52 are provided with downwardly and diagonally extendin portions 53-54 respectively, the lower ends of which terminate at the reed 55 in the horizontal plane of the stationary arms 56 and 51 and are each provided with downward extending portions 58 and 59 respectively which are secured to the reed 55 in the usual manner.

Both of these types of movable contact arms are especially adapted for low frequency work as will be understood because they will produce the maximum wipe and roll of the contacts whereas in the preferred embodiment, the construction is designed primarily for high frequencies wherein the contacts have a small amount of wipe and roll.

It is to be understood that some of the details described may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

We claim:

1. In a vibrator, a one-piece laminated frame comprising a base, an upright member and a pole piece, an electromagnet attached to said pole piece, a reed anchored to said frame base, an

armature-weight carried by the free end of said reed, a pair of relatively rigid oppositely extending contact arms attached to said reed near the base of said frame and extending at right-angles thereto, a contact on the free ends of each of said arms depending therefrom a pair of cooperating relatively rigid and oppositely extending stationary contact arms anchored in the base of said frame and extending in a plane parallel to the plane of said movable contact arms, and a contact on the free ends of each of said arms extending upwardly therefrom.

2. In a vibrator, a frame made upon a series of laminations comprising an upright, a base and a pole piece; an electromagnet attached to said pole piece; a vibrating reed rigidly anchored at one end to said base and having a transversely extending slot therein adjacent said point of attachment to said base, an armature-weight anchored to the free end of said reed; a pair of relatively rigid contact arms anchored to said reed adjacent to and above the slot and each extending oppositely at right-angles to said reed; a pair of contacts for said arms, one attached to the bottom side of the free end, of each contact arm; a pair of relatively rigid stationary contact arms anchored at one end in said base at opposite sides thereof, the other end being arranged to extend in a plane parallel to said reed arms and positioned below and aligned with said reed arms; a pair of contacts for said stationary contact arms, one attached to the top side of the free end of each said stationary contact arm and in alignment with said reed arm contacts, and a plurality of spacers interposed. between said stationary contact arms and said frame base.

3. In a vibrator, a frame comprising a base, an upright member and a pole piece, an electromagnet attached to said pole piece, a reed anchored to said frame base, an armature weight carried by the free end of said reed, a pair of relatively rigid oppositely extending contact arms attached to said reed near the base of said frame and extending at right angles thereto, a contact on the free ends of each of said arms depending therefrom, a pair of cooperating relatively rigid and oppositely extending stationary contact arms extending in a plane parallel to the plane of said movable contact arms and a contact on the free ends of each of said arms extending upwardly therefrom.

STEPHEN F. JAMES. ESTHER D. JAMES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,535,088 Barnhart Apr. 28, 1925 2,072,578 Barrett et a1. Mar. 2, 1937 2,185,950 Rose Jan. 2, 1940 2,190,685 Slater Feb. 20, 1040 2,280 023 Barrett Apr. 14, 1942 2,364,684 Aust Dec. 12, 1944 2,372,965 Lord Apr. 3, 1945 FOREIGN PATENTS Number Country Date 550,975 Great Britain Feb. 2, 1943 

